package com.kqzz.common.exception;

import com.google.gson.Gson;
import com.kqzz.common.api.response.Response;
import lombok.extern.slf4j.Slf4j;
import org.apache.commons.lang.StringUtils;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.security.authentication.BadCredentialsException;
import org.springframework.security.core.Authentication;
import org.springframework.security.crypto.codec.Base64;
import org.springframework.security.oauth2.common.OAuth2AccessToken;
import org.springframework.security.oauth2.common.exceptions.UnapprovedClientAuthenticationException;
import org.springframework.security.oauth2.provider.*;
import org.springframework.security.oauth2.provider.token.AuthorizationServerTokenServices;
import org.springframework.security.web.authentication.SavedRequestAwareAuthenticationSuccessHandler;

import javax.servlet.ServletException;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import java.io.IOException;
import java.util.HashMap;

/**
 * 登录成功处理
 */
@Slf4j
//@Component("customAuthSuccessHandler")
@SuppressWarnings("deprecation")
public class CustomAuthSuccessHandler extends SavedRequestAwareAuthenticationSuccessHandler {

	@Autowired
    private ClientDetailsService clientDetailsService;

	@Autowired
    private AuthorizationServerTokenServices authorizationServerTokenServices;

	@Override
	public void onAuthenticationSuccess(HttpServletRequest request, HttpServletResponse response, Authentication authentication)
			throws ServletException, IOException {
		log.info("");

		response.setContentType("application/json;charset=UTF-8");
        Gson gson = new Gson();

        String header = request.getHeader("Authorization");
        if (header == null || !header.startsWith("Basic ")) {
            throw new UnapprovedClientAuthenticationException("请求头中无client信息");
        }
        String[] tokens = this.extractAndDecodeHeader(header, request);

        assert tokens.length == 2;

        //获取clientId 和 clientSecret
        String clientId = tokens[0];
        String clientSecret = tokens[1];

        ClientDetails clientDetails = clientDetailsService.loadClientByClientId(clientId);

        if (clientDetails == null) {
        	response.getWriter().write(gson.toJson(new Response().failure("clientId 对应的配置信息不存在")));
        	return ;
        }else if (!StringUtils.equals(clientDetails.getClientSecret(),clientSecret)){
            response.getWriter().write(gson.toJson(new Response().failure("clientSecret 不匹配")));
        	return ;
        }

        TokenRequest tokenRequest = new TokenRequest(new HashMap<>(), clientId, clientDetails.getScope(), "authorization_code");
        OAuth2Request oAuth2Request = tokenRequest.createOAuth2Request(clientDetails);
        OAuth2Authentication oAuth2Authentication = new OAuth2Authentication(oAuth2Request, authentication);
        OAuth2AccessToken token = authorizationServerTokenServices.createAccessToken(oAuth2Authentication);

        response.getWriter().write(gson.toJson(new Response().success(token)));
	}

	/**
     * 解码请求头
     */
    private String[] extractAndDecodeHeader(String header, HttpServletRequest request) throws IOException {
        byte[] base64Token = header.substring(6).getBytes("UTF-8");

        byte[] decoded;
        try {
            decoded = Base64.decode(base64Token);
        } catch (IllegalArgumentException var7) {
            throw new BadCredentialsException("Failed to decode basic authentication token");
        }

        String token = new String(decoded, "UTF-8");
        int delim = token.indexOf(":");
        if (delim == -1) {
            throw new BadCredentialsException("Invalid basic authentication token");
        } else {
            return new String[]{token.substring(0, delim), token.substring(delim + 1)};
        }
    }
}
